Exhaust manifold device



April 3, 1951 c. R. FLlNT EXHAUST MANIFOLD DEVICE' Filed April 29, 1947 Patented Apr. 3, 1951 UNITED STATES PATENT OFFICE? 2,547,454 EXHAUST MANIFOLD DEVICE Charles R. Flint, La Porte, Ind. Application April 29, 1947, Serial No. 744,582

13 Claims.

This invention relates to a vacuum accumulator, and more particularly to a vacuum accumulator intended for application to an exhaust manifold of an internal combustion engine.

It is well known that following the explosion of a charge in a cylinder of an internal combustion engine of the 4-cycle type and the opening of the exhaust valve, the compressed burnt gases tend to evacuate the cylinder as a mass leaving in their wake a void within the cylinder. In the ordinary type of internal combustion engine, the void is partially replaced by exhaust gases returning to the cylinder. The succeeding charge, when drawn into the cylinder, then becomes partially mixed with burnt gases from the preceding explosion with the resulting lessening in the eiliciency of the engine.

I have invented, and am herein disclosing and claiming a vacuum accumulator adapted to be attached tothe exhaust manifold of an internal combustion engine which in its operation supplies fresh air via the exhaust manifold to the cylinder immediately after the evacuation of the burnt gases therefrom. Inasmuch as fresh air is introduced to the cylinders in place of returned burnt gases as in previous constructions, the eciency of the engine is greatly increased with a resulting saving in power and fuel.

The present device includes two valves, which have been found to prevent clouding of the de-` vice with moisture due to escape of some exhaust gas past a single check valve while it is still open.

The device has also been found to produce a fog of condensed moisture during times of decompression within the tube, and this phenomenon is particularly associated with the stepped portions of the tubing, where the expansion occurs. It is obvious that to increase this function without producing clogging of the tube with moisture, the device should be mounted in a relatively cool position in the engine, and the tube itself should be relatively unencumbered to'provide a steady escape of gases through it.

It has been found in actual operation of the device in automobiles, that the exhaust valves of cylinders connected to the exhaust manifold are maintained remarkably clean. This appears to be a function of the condensed moisture produced within the tube or accumulated, which is carried within the cylinders during fluctuations of pressure within the system.

This application is a continuation-impart of my copending applications Serial No. 559.824, filed October 21, 1944, now Patent No. 2,482,750, and

Serial No. 718,721, filed December 27, 1946, now abandoned.

The condensation of moisture is increased if the tube used is not connected with the atmosphere, but the device does not then have some of its other advantages.

The invention will be described as embodied in the accompanying drawing in which The housing chamber is shown as comprising four f parts, the end I3, the union I4, the chamber housing I 5 and the end closure I6. It will be noted that the housing forms a housing chamber I 'I about the tube I0 which chamber is not greatly larger than the tube. For example, with a tube g in internal diameter, the entire housing chamber is suitably not much more than 1/2 in diameter. The tube I0 terminates slightly short of the end I6 of the housing. The tube I0 is about l2 inches long and the effective length of the chamber4 I'I about '7 inches about 9 inches. i

The division shown for the housing is preferred for ease of assembly. Tt is obvious that the entire device may be made in one piece, if desired.

Communicating with the housing chamber is an air reservoir, generally designated as I8 which has a threaded end i9 threading into the union I4, a right angular curved portion 2l), a reservoir portion 2I, and an air filter 22. The reservoir portion ZI is defined between the check valves 23 and 24.

Each check valve comprises an annular valve seat 25 against which a neoprene diaphragm 26 and a metal diaphragm 21 are pressed by a very light leaf spring 28. The diaphragm has a larger diameter than the valve seat 25 so that its edges project thereover into the space 29. 'I'he check valves are so arranged that air is permitted to flow in one direction only through opening 30, that is in a direction from the air filter towards the housing chamber I 1. The diaphragms are lightly constructed so as to have substantially no inertia. The air lter 22 is of usual construction,f comprising a cover 3l, a housing 32, an air cleaner screen 33 renclosing a filter material 34.

Also Vcommunicating with the housing is a surge l and the tube I8 chamber 39 communicating with the housing chamber through an opening 36 which is partially closed by a diaphragm 31 having an opening .38 therein. The chamber is closed by a plug 6). The surge chamber serves as an additional vacuum accumulator.

A clamp 4I serves to hold the air reservoir I8 against excessive vibration.

The figures in the drawing are drawn to scale, the size being of considerable importance, although the spacing and size may vary in accordance with the particular motor with which the device is associated.

Having described the structure of my invention, its operation will now be explained. The exploded gases within the cylinder of an internal combustion engine are under pressure. The opening of the exhaust valve initiates the hereinabove mentioned effect in the gases will therey upon tend to evacuate the cylinder as a mass,

leaving a void in their wake. The mass of compressed gases, upon entering the exhaust manifold of the engine, momentarily increase the pressure within the manifold and hence compress the air within the tube I and the chamber Il which are connected to the exhaust manifold. Upon the passing of the compression wave of exhaust gases, a resulting lower pressure area is left in their wake. The tube I0 and the chamber Il are exposed to this area of reduced pressure and the air therefore is subjected to the same physical laws, and will tend to evacuate the tube and chamber as a mass and rush into the manifold and thence into the cylinder recently evacuated by the exhaust gases. structions, the void left behind in the tube and housing chamber tended to draw the air back into the tube and hence decrease the amount of air remaining within the cylinder. The present invention overcomes this tendency by the provision of the air reservoir I8. Air evacuating the tube and chamber creates an area of lesser pressure within the tube and chamber which causes the valve 23 to open. The air within the reservoir portion 2l is then subjected to the same physical laws. It has been opened to an area of lesser pressure. The air within the reservoir portion thereupon rushes into the housing chamber and tube replacing a portion of the air recently evacuated therefrom, therein and greatly reducing the tendency of air to return to the tube. The decrease of the pressure within the reservoir portion 2i opens the valve 2d and the reservoir, tube and chamber are recharged by air from the atmosphere in readiness for the next cycle.

The presence of two valves 28 and '24 is of particular value in preventing noisiness of the system. The single valve 26 would permit, under some conditions, direct passage of air under conditions which would produce noise.

I The air filter is provided to screen foreign particles from the vacuum accumulator to prevent damage to the valves or to the engine itself. The drawing herein is substantially to scale.

While I have shown and described my inven t1on 1n its preferred embodiment, it is to be un derstood that it is capable of many modifications. Changes, therefore, in the construction and arrangement may be made without departmg from the spirit and scope of the invention as disclosed in the appended Claims,

I claim:

1. A vacuum accumulator comprising: an elongated open-ended tube at least ten times as long In my said previous coni" increasing the pressure r as its diameter, said tube being adapted to be connected to the exhaust manifold of an internal combustion engine, a housing chamber about the tube, an opening from the tube to the chamber, an air reservoir connected to the chamber, said reservoir having an opening to said chamber and an opening to the atmosphere, and means associated with said reservoir permitting a flow of air therein in a direction toward said chamber only.

2. A vacuum accumulator comprising: an elongated open-ended tube at least ten times as long as its diameter, a housing chamber about the tube, said tube being adapted to be connected at one end to the exhaust manifold of an internal combustion engine and opening at the other end to the chamber, an air reservoir communicating with the chamber and with the atmosphere and means within said reservoir permitting a flow of air therein in a direction toward said chamber only.

3. The vacuum accumulator of claim 2 in which said' flow permitting means comprises a rst valve adjacent the opening of the reservoir into the' f chamber and a second valve adjacent the open-t ing of the reservoir to the atmosphere.

4. The vacuum accumulator of claim 2 in which said reservoir is a pipe being at least ten times' as long as its diameter.

5. A vacuum accumulator comprising: an elongated open-ended tube at least ten times as longV as its diameter, a housing chamber about the tube, said tube being adapted to be connected at one end thereof to the exhaust manifold of, an internal combustion engine and the other end of said tube opening to said chamber, an air' reservoir comprising a pipe at least ten times asl long as its diameter opening at one end thereof to said chamber and opening to the atmosphere at the other end, a first check valve having a diaphragm of no substantial inertia within said pipe adjacent the chamber end thereof, and a second check valve having a diaphragm of no substantial inertia adjacent the other end of said pipe.

6. The vacuum accumulator of claim 5 including a blow-out plug communicating with said chamber.

7. The vacuum accumulator of claim 5 including an air filter mounted on the pipe adjacent the other end thereof.

8. The vacuum accumulator of claim 5 in which the housing chamber extends substantially the entire length of the tube.

9. In an internal combustion engine having a plurality of cylinders operatively connected to an exhaust manifold, a vacuum accumulator, comprising: an elongated open-ended tube at least ten times as long as its diameter, one end of said tube being connected to the exhaust manifold, a housing chamber about the other end of the tube, a pipe at least ten times as long as its diameter opening to said chamber at one end and opening to the atmosphere at the other end, a rst check valve having a diaphragm of no substantial inertia within said pipe adjacent the chamber end thereof, and a second check valve having a diaphragm of no substantial inertia adjacent the atmosphere end of said pipe, said pipe and check valves being adapted to admit air through said tube to the exhaust manifold during operation of the engine.

10. An accumulator as set forth in claim l including a surge chamber attached to the housing chamber and Opening thereto through a restricte@ opening,

11. In an engine of a four cycle type having a plurality of cylinders communicating with an exhaust manifold through exhaust valves, a Vacuum accumulator, including: an elongated openended tube connected at one end to said exhaust manfold, said tube being at least ten times as 1ong as its greatest diameter, an air reservoir pipe communicating with the other end of said tube, said tube being exposed to intermittent increases in pressure within said manifold during operation of the engine to cause compression of the air within the tube, expansion of the air so compressed producing a fog of condensed moisture.

12, In an enginev as set forth in claim 11 the further feature that said pipe is closed at its remote end by an inwardly opening check valve of no substantial inertia.

pipe.

CHARLES R. FLINT.

` REERENCES CITED The following references are of record in the file of this patent:

UNITED STATES PATENTS Number Name Date 2,295,907 Lewis Sept. 15, 1942 2,390,527 Flint Dec. 11, 1945 

